Can a Burst of UV Bust Hospital-Borne Infections?

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Katherine Harmon Courage is a freelance writer and contributing editor for Scientific American. Her book Octopus! The Most Mysterious Creature In the Sea is out now from Penguin/Current. Follow on Twitter @KHCourage.

Nasty Clostridium difficile can lurk on door handles and other surfaces, leading to severe intestinal distress; Acinetobacter can also survive in the open air, threatening to cause pneumonia, urinary tract infections and blood infections; and vancomycin-resistant Enterococci (VRE) is tough to beat with other drugs and can infect wound and catheter sites, as well as the bloodstream. Even a thorough traditional cleaning by staff, with disinfecting sprays, can leave spots untouched—and dangerously contaminated.

A new study finds that a certain frequency of ultraviolet (UV) light can kill almost all of these nasty bugs from at least the surfaces of a hospital room—even when not directly exposed to the light.

A team of researchers sampled five high-contact areas in hospital bedrooms and bathrooms (such as bed rails, toilets and remote controls) where patients with C. difficile, Acinetobacter or VRE infections had been staying. They then brought in a machine outfitted with eight bulbs to emit short-wave UV radiation (UV-C) for 25 to 45 minutes. Afterward, the researchers sampled the same locations for any persisting bacteria or spores.

“We were able to demonstrate that we could achieve well over 90 percent reduction in each of those three bad bugs after using the UV light,” Deverick Anderson, co-director of the Duke Infection Control Outreach Network, and study collaborator, said during a media briefing call earlier this week. Even shadowed surfaces that escaped direct UV exposure demonstrated this drastic reduction in bacteria. The findings were presented October 18 at IDWeek, a meeting to highlight progress in the fight against infectious diseases, in San Diego.

UV-C radiation has already been deployed by food processors and utilitiesto kill bugs in food and water, respectively—and it is also used to sterilize some medical equipment. Putting it to use for larger targets—such as hospital rooms—might become a new standard step in healthcare disinfection. The researchers did not, however, compare the light’s effectiveness with that of standard cleaning procedures. “We would never propose that the UV light be the only form of room cleaning,” Anderson said in a prepared statement. “But in an era of increasing antibiotic resistance, it could become an important addition to hospitals’ arsenal.”

Previous work had shown that UV-C can also cut down on MRSA (methicillin-resistant Staphylococcus aureus) in hospital rooms. “We have a solid foundation to show that this approach succeeds in both experimental and real-world conditions,” Anderson said in a prepared statement. “Now it’s time to see if we can demonstrate that it indeed decreases the rate of infections among patients.” After all, it would be nice to be rid of our acquired infection risk in a flash.

About the Author: Katherine Harmon Courage is a freelance writer and contributing editor for Scientific American. Her book Octopus! The Most Mysterious Creature In the Sea is out now from Penguin/Current. Follow on Twitter @KHCourage.

2 Comments

I think adding UV disinfection lights to hospitals is an excellent idea, especially since hospital acquired infections are one of the top five causes of death in the U.S. Portable UV disinfection wands could easily be used by hospital janitors to disinfect the bathrooms and hospital beds. The only drawbacks I can see are that UV lights can produce sunburn,skin cancer, and eye damage if exposed directly onto humans. Also, I believe UV like can produce Ozone, which can be harmful to human health, so studies on those negative aspects of the lights should be studied more before it is fully adopted by all hospitals. And, UV light causes plastics and rubber to break down quickly, so hospitals that use UV light disinfection should consider that before shining them on plastic or rubber surfaces.

As the article states correctly, the utility of UV light is limited to surface disinfection. What about areas such as sink drains where UV light cannot penetrate but which are known sources of bacterial growth and spread through aerosols? Fortunately, there are other technologies that are specific to sinks that work continuously without consumables or human intervention. Visit Kleanik for details.